#! /usr/bin/env bash
###### Default environment variables ######
STOPWATCH_LABEL=${STOPWATCH_LABEL:-stopwatch}
TIMER_LABEL=${TIMER_LABEL:-timer}
DEFAULT_MODE=${DEFAULT_MODE:-timer}
DEFAULT_STOPWATCH=${DEFAULT_STOPWATCH:-0}
DEFAULT_TIMER=${DEFAULT_TIMER:-60}
PLAY_LABEL=${PLAY_LABEL:-(playing)}
PAUSE_LABEL=${PAUSE_LABEL:-(paused)}
TIMER_LOOP=${TIMER_LOOP:-false}
NEUTRAL_COLOR=${NEUTRAL_COLOR:-#000000}
###### Default environment variables ######

###### Functions ######
error() {
  echo Error: "$@" 1>&2
}

next_mode() {
  mode=$(( (mode + 1) % ${#modes[@]} ))
  set_mode
}

play_pause() {
  $running && pause || play
}

play() {
  running=true
  status_symbol=$PLAY_LABEL
}

pause() {
  running=false
  status_symbol=$PAUSE_LABEL
}

reset_times() {
  unset time
  set_mode
}

set_mode() {
  case ${modes[$mode]} in
    'timer' )
      running=false
      status_symbol=$PAUSE_LABEL
      initial_time=${initial_time-$DEFAULT_TIMER}
      time=$initial_time
      incr=-1
      ;;
    'stopwatch' )
      running=false
      status_symbol=$PAUSE_LABEL
      time=${time-$DEFAULT_STOPWATCH}
      fgcolor='#FFFFFF'
      bgcolor=$NEUTRAL_COLOR
      incr=1
      ;;
  esac
}

compute_color() {
  t=$1
  hue360=$(( 120*t/initial_time ))
  tmp=$(( hue360 % 120 - 60 ))
  tmp=$(( (60 - ${tmp#-})*255/60 ))
  if (( hue360 < 60 && hue360 >= 0 )); then
    R=255 G=$tmp B=0
  elif (( hue360 <= 120 && hue360 >= 60 )); then
    R=$tmp G=255 B=0
  fi
  printf '#%06X\n' $(( R*16*16*16*16 + G*16*16 + B ))
}

prettify_time() {
  seconds=$time
  if (( time >= 60 )); then
    minutes=$(( time / 60 ))
    seconds=$(( time % 60 ))
    (( seconds < 10 )) && seconds=0$seconds
  fi
  if (( minutes >= 60 )); then
    hours=$(( minutes / 60 ))
    minutes=$(( minutes % 60 ))
    (( minutes < 10 )) && minutes=0$minutes
  fi
  echo $hours${hours+:}$minutes${minutes+:}$seconds
}
###### Functions ######

###### Internal variables ######
modes=([0]='timer' [1]='stopwatch')
labels=([0]="$TIMER_LABEL" [1]="$STOPWATCH_LABEL")
###### Internal variables ######

###### First run initialization ######
if [[ ! -v time ]]; then
  for i in "${!modes[@]}"; do
    if [[ "${modes[$i]}" == "$DEFAULT_MODE" ]]; then
      mode=$i
    fi
  done
  set_mode
fi
###### First run initialization ######

###### Click processing ######
case $BLOCK_BUTTON in
  1 )
    play_pause
    ;;
  2 )
    reset_times
    ;;
  3 )
    next_mode
    reset_times
    pause
    ;;
  4 )
    $running && pause
    initial_time=$(( initial_time + 1 ))
    time=$initial_time
    ;;
  5 )
    $running && pause
    initial_time=$(( initial_time - 1 ))
    time=$initial_time
    ;;
esac
###### Click processing ######

###### Time increment ######
$running && time=$(( time + incr ))
if (( mode == 0 )); then
  if (( time <= 0 )); then
    bgcolor='#FF0000'
    fgcolor=$NEUTRAL_COLOR
    time=0
    pause
  elif (( time > 0 )); then
    fgcolor=$(compute_color $time)
    bgcolor=$NEUTRAL_COLOR
  fi
else
  bgcolor=$NEUTRAL_COLOR
  fgcolor='#FFFFFF'
fi
full_text="${labels[$mode]} $status_symbol $(prettify_time)"
if (( mode == 0 && time == 0 )); then
    $TIMER_LOOP && reset_times && play
fi
###### Time increment ######

###### Output ######
cat << EOF
{"full_text":"$full_text",\
"status_symbol":"$status_symbol",\
"time":"$time",\
"initial_time":"$initial_time",\
"incr":"$incr",\
"running":"$running",\
"mode":"$mode",\
"color":"$fgcolor",\
"background":"$bgcolor"}
EOF
###### Output ######